It is clearly inspired by Factorio, but just from seeing the list of basic resources, it's just a clone.

That said, given there are already games with similar mechanics, such as "FortressCraft Evolved", "Factory Idle", "Mindustry", and the devs explicitly approved of "Satisfactory" I doubt they would care.

Past that, Factorio started as an attempt to create a standalone expansion of several minecraft tech mods, like Buildcraft and Industrialcraft, but focusing in a different direction. So it isn't even pretending to be fully original (not that such a thing exists in the first place)